janus-analyzer-skill

name: janus-analyzer-skill description: Use this skill for Janus requests that ask what to measure, how to measure it, which analyzer should answer it, or how to implement or adjust source-aware analysis for Mythic or Ghostwriter telemetry.

Janus Analyzer Skill

Overview

Use this skill when the user wants Janus to answer a measurement question, design a new metric, extend an analyzer, or explain why a result differs between Mythic and Ghostwriter.

Start from the existing Janus execution path instead of inventing new analysis flows. Read only the source-specific reference that matches the request.

Workflow

1. Pin down the question to answer in one sentence.
2. Determine the source: mythic, ghostwriter, or compare both. If the source is omitted, infer it from the task or config only when low-risk.
3. Read these core files first:
   • janus.py
   • Core/analyzer_registry.py
   • Core/analyzer_behavior_registry.py
   • Config/analyzers.yml
   • Config/analyzer_registry.yml
4. Route by source:
   • Mythic: read Parsers/Mythic/mythic_pull.py
   • Ghostwriter: read Parsers/Ghostwriter/main.py
   • Cobalt Strike REST: read Parsers/CobaltStrike/cobalt_strike_rest.py
   • CobaltStrike TSV: read Parsers/CobaltStrike/cobalt_strike_tsv.py
   • Partial Mythic: read Parsers/Mythic/partial_data_adapter.py
   • Cross-source comparison: read docs/architecture.md then parser files above
5. Classify the request before editing code:
   • Existing analyzer usage or report interpretation
   • Behavior-registry tweak
   • Parser normalization gap
   • New analyzer
6. Prefer the smallest change that answers the question cleanly.

Implementation Rules

• Keep analyzer names in kebab-case and register outputs in Core/analyzer_registry.py.
• For a new analyzer, update all runtime registration points:
  • Core/analyzer_registry.py
  • Config/analyzers.yml
  • janus.py ANALYZER_FUNCTIONS
  • janus.py run_analyze()'s explicit analyzer dispatch branch
• Preserve the canonical task/result event model Janus already uses.
• Treat Ghostwriter result state as unreliable unless the source schema actually adds trustworthy status fields.
• Do not “equalize” Mythic downward; source-aware behavior should degrade weaker sources safely, not discard stronger Mythic fidelity.
• If a metric depends on success/error truth, say explicitly whether Ghostwriter can support it today.
• If only heuristics need adjustment for known commands, prefer Config/analyzer_registry.yml over hard-coding special cases.
• Always update Core/html_output.py when an analyzer's output schema changes. Find the _render_<analyzer_name> function and update any .get(“key”) references that no longer match. Silently empty tables are the failure mode.
• After adding a new analyzer, run it once through the real CLI/container path, not just direct Python imports, to catch missing run_analyze() registration.
• Parser robustness guardrails now exist and should be preserved:
  • normalize_timestamp() accepts ISO and epoch values; malformed timestamps should be handled intentionally (skip with counters or raise early).
  • load_events() can validate schema and warns on unknown event types.
  • run_merge() remaps missing/duplicate operation_id values to deterministic unique IDs to avoid cross-operation key collisions.

What Good Output Looks Like

When answering the user, produce:

• The metric or question being answered
• The source scope and any fidelity limits
• Whether Janus already supports it or needs code changes
• If code changes are needed, the minimal files to touch

References

• docs/architecture.md